angst

Angst, depending on the context, may have different meaning. In this write up, I will broadly discuss both the scholary and colloquial use of the term. However, I will start by describing the etymology of the word.
start by describing the etymology of the word.

Angst is a word occurring in German, Dutch, and the
Scandinavian languages. In German1 and Dutch it
means fear, nothing more, nothing less. The word actually
has its roots in Latin2, specifically the word
angustus3, which means narrow or
confined. The Dutch word eng also reflects this,
as this word can mean both scary and confined. Imagine
how fear makes your chest feel all clenched up, if you
will.

The word angst was introduced in the English language in
1849 by George Elliot4. Its use became popular by
the the translation of the works of existentialist
philosophers. For them, the concept of angst meant a deep
and essentially philosophical anxiety about the world in
general or personal freedom 5. The word was used
between quotes to indicate it was jargon.

In the 1940s, the word came into more general usage. In
particular, the phrase teenage angst caught on. If you
would have to use a synonym for angst in this context,
anxiety would come close-which is not surprising given the
similar etymology. Generally, it means something like a
general state of fear and depression. Wallowing in
self-misery is implied, and the term is generally a
pejorative.

In summary, angst started out as a specific piece of
existentialist jargon, introduced into the English language
in the middle of the 19th century. It generally lost its
specific meaning, and became a general descriptor of
anxiety with some depression mixed in5.

PS According to our esteemed Glowing Fish:

it doesn't make much sense to say that angst was introduced into the English language as a piece of existentialist jargon in the mid-19th century, since it was used philosophically by Kierkegaard, writing after George Elliot, and Kierkegaard did not, AFAIK, have a large readership in England. And the world only came into its own with Heidegger in the 1920s.